Lifting a 2WD?

[DKasper]

Hi Guys,

It's been quite a switch going from a '99 QC 2500 4x4 to my current '93 2x4 D350. I think I can get along with the 2WD as far as traction is concerned, but what I really miss is the ground clearance. I seem to be scraping things every time I go out in a pasture or am off the pavement.



Has anyone put something like a 2" lift on a 2wd? It looks like if I could lift it a bit, then maybe I could move up from the 215/85 tire to a 235/85 to get even a little more clearance. I guess I'd be concerned about driveline angles and steering geometry -- I know nothing about lifts!



Thanks for your ideas!



Dave

'93 D350, auto, Westach pyro/boost, pump tweaked a bit

 

[cerberusiam]

The 235/85 tires should be what the truck came from the factory with. I am running 255/85's on mine and with the heavy duty springs in the front it sits almost as high as 1/2 4x4. To date date I have not found any spindles that I would trust to raise the front end for more clearance. I am sure with enough money you could have some built but with that much weight in the front end and the fact the ball joints and springs are barely adequate I would be a little worried about the extra leverage. A 2 inch body lift would help with tire clearance for bigger tires but then the fan shroud and the AC (if present) lines will need to be lengthened. I now have enough clearance to be able to roll under the whole truck on a creeper with room to spare. If you just change to a taller tire and heavier springs in the front you will be surprised at the difference. I can turn out thru about any road ditch and not scrape any part of the undercarriage.



As a side note my truck likes the taller tire a lot better for power and mileage. The trans doesn't like it but its getting replaced.

 

[DKasper]

Cerberusiam,

Thanks for the info! Good point about the spindles. I wish I could get a creeper under mine!



I bought my rig used and the 215's are just what were on it. I've heard that I can go to the 235's without having to use a spacer in the back, and 255/85's with a spacer. But it looks like the front end would definitely have to be higher to handle that.



Question: Did you use any particular brand of heavier spring, or did you just go to NAPA and get whatever they had?



Also, did you do anything to the back end to raise it, or did the heavier fronts just about level it out?



Thanks!

Dave

 

[cerberusiam]

Unless they have changed the suspension from 92 to 93 you won't need a spacer in the back. I am confused about the spacer thing because there is more than ample room in the rear for a much bigger tire. You would have to really load the backend to get enough spring sag to even approach a rub condition. The only difference could be the weight ratings for the axles. Mine is a 4000 lb front and a 5450 lb rear. Might check the ratings just to be sure they are the same.



The springs I used are a Moog 7226s part number. When they were new they just leveled the truck. After a couple years they have sagged about 1 inch with the beating the stinkin' rough roads around here are doling out. Still plenty of clearance and with a lighter tire the ride and handing is great. The 255/85 tires will fit and work fine with only a little rub on the fender flares if you bounce it on a hard turn. Had to recenter the front sway bar as one side was touching a little.



Unless you are hauling a lot of weight I would definitely stay away from the heavier tires. Mine rides like a caddy, with a ton in the box and a 7000 lb trailer on the bumper. The taller tire have a much stifer sidewall so unloaded the ride is about like the 4x4 version.



Since I still have a little sag in the front I am trying something to help the ride and keep it level. Firestone makes an air bag to go inside the front coil spring. It is listed for the 94 and up 2x4 but the spring dimensions are almost the same as the 92. I need to relocate the shocks outside the spring but thats trivial.



The other issue I am seeing has two possible causes. The heavy tall tires or the ride height. Either the heavy tires are just causing a lot of vibration or I need some air dams to redirect the air flow from under the truck. I am seeing a lot more vibration that seems worse when going into a stiff headwind.



The way my motor is setup it likes a taller tire for power and mileage. I am thinking the best combo would be a set of 265/75 tires with the truck leveled and add a lockup converter to get rpm's down.



One other thing, with the extra spring the lower ball joints take a beating. They need to be replaced with a good unit. I think I may have wasted another one with heavy tires and rough roads. Still playing with combinations to find the best one.

 

[DKasper]

Thanks for the part number on the springs. I called NAPA and they crossed the moog number to a Dana part. Spring thickness is 0. 9" - -wow! Pretty thick springs. They wanted $131 for a pair.



If I remember, there was a post that referenced an oversized Moog ball joint that fit our application. I'll have to do some searching on that one.



Unfortunately my tires are almost new - only about 12,000 miles on them. Guess I'll just have to do more driving!



Thanks for your help,



Dave

 

[cerberusiam]

I think the oversize ball joint was to repair the worn out threads on the upper ball joint but don't remember for sure.



I paid $150/pair for the moog springs so $131 is in the ball park.



As for the tires, take it out on the back roads and "true" the tires up a couple of times then you can justify a new set.



I wore out a rear set in about 15k on mine, and they were studded. Didn't have any studs left and the centers were kinda thin. Gotta love that cummins TQ.

 

[Greenleaf]

Tire Size/Springs

Hi guys! This subject is especially interesting because I'm in the same boat. My front springs are sagging. Truck runs down hill all the time I asked my local alignment shop to R&R the springs for me but he said that he is too close to retirement to tackle a job like this. Besides, according to him, the Dodge with a CTD is too heavy for his equipment . He must see a lot of Escorts and Neons. I will try to R&R them myself.



A question about tire size. I purchased mine with 245/75 I have no clue what this means,notta,none,zippo. The factory is 235/85. Again,no idea. It would seem to me that the 245/75 is smaller,thus turns slower . The 235/85 is larger and turns faster????????? The engine runs faster with a small tire and runs slower at a given speed with the larger tire???? Or am I all wet?



Bottom line is, my speed-o is way off.

When my meter reads 60 MPH, I'm only going 55. Would it benefit me to replace my current size with something different, or replace with factory size? I'm speaking in terms of fuel economy/power to the pavement etc. etc.



Scott

 

[Clarkoh]

19.5's

This is interesting. I got excited about the thought of tires that would haul the weight and last forever. Got a set of 19. 5 wheels and some 225-70 19. 5 tires. So far I have not tried new tires. Got a deal on about 11- 19. 5's and am using them up first.



Because they were used (from a mini motorhome) they had some minor cupping on them. The front springs on my 2WD are not adequate and niether are the Koni shocks (set as stiff as they will go). If there is the slightest irregularity in the tire, it is amplified by the heavy tire/wheel and turns into major cupping!!



I am thinking of putting these wheels on Ebay and getting a nice light weight set of aluminum wheels and some big 16's for it! Shipping will be something. The four of them weight in at 400 lbs.

 

[Greenleaf]

Tire Size

Got me an ejucashun this weekend at the trade show.



245/75. The 245 is sectional width. A tire at 215 is narrower than 234 and so on. The 75 is side wall profile, in percentage of section width. 75 is shorter than 85 and so on.



Bottom line; a 245/75 tire is wider than the factory 235, but shorter than the factory 85. this is represented in MM.



A smaller tire [shorter] will turn faster than a larger [taller] tire at a given speed. Taller tires last longer because they have a larger rolling radius,[farther distance around].



This is why my speed-o is off, my tires are smaller around.



Professor Scott

 

[cerberusiam]

Scott



You got it. The tires you have are about an inch shorter than the stock tires. The 245/75 is 30. 4 inches and the 235/85 is 31. 6 inches. Here is the formula for converting metric sizes to something thats understandable:



(face width * sidewall height * 2)/2550 + wheel size



(245 * 75 * 2)/2550 + 16 = 30. 4





The sidewall height is a percentage of face width. A 75 series tire has a sidewall height 75% of face width.



The typical adjustment for the speedo gear is 2. 5 mph per tooth up or down. If you increase your speedo gear by 2 teeth it should put your speedo about where it needs to be. I went 1. 5 inches up in sive and it works out to about the same by the odometer. Check your odometer on a measured mileage also since there can be some discrepencies.



Changing the springs out is not that big of a job. A 3 lb hammer, pickle fork, and a good floor jack is about all you need to do it. I have no idea why the alignment shop thinks its a big deal but there is probably more money in the motorized roller skates than a decent sized vehicle. If your even half way handy you swap springs easily.



The thing I am finding out about these taller tires is they are sensitive to balance and alignment. Either of these out very far tends to get multiplied by the circumference. It doesn't take much to cause a vibration or start them cupping. You need to make sure the tire shop does a good balance job, no stinking static balance and glue on weights with custom wheels, and make sure the ball joints are good and alignment is good.

 

[Greenleaf]

Yes... ... ... ... ... ... ... ... . I second that